(physical chemistry is the domain which ... is member of) (chemistry) a surface forming a common boundary between two things (two objects or liquids or chemical phases)

(physical chemistry is the domain which ... is member of) (physical chemistry) the pressure exerted by a solution necessary to prevent osmosis into that solution when it is separated from the pure solvent by a semipermeable membrane

(physical chemistry is the domain which ... is member of) (physical chemistry) a distinct state of matter in a system; matter that is identical in chemical composition and physical state and separated from other material by the phase boundary

"the reaction occurs in the liquid phase of the system"

(physical chemistry is the domain which ... is member of) (physical chemistry) a fourth state of matter distinct from solid or liquid or gas and present in stars and fusion reactors; a gas becomes a plasma when it is heated until the atoms lose all their electrons, leaving a highly electrified collection of nuclei and free electrons